COVID-19Phase 4DAN-COVIDNCT07279766
Effectiveness of mRNA-1273 Variant-Containing Vaccine Formulation Against Severe Outcomes in Adults Aged 50-64 Years Without Risk Factors for Severe COVID-19
A Phase 4 study testing mRNA-1273 (Moderna COVID-19 vaccine) in people with COVID-19, run by Tor Biering-Sørensen at 2 sites in Denmark.
Trial summary
The purpose of this pragmatic randomized trial is to evaluate the vaccine effectiveness of the COVID-19 vaccine, mRNA-1273, in adults aged 50-64 years without known risk factors for severe COVID-19 infection. Participants will be randomized 1:1 to either COVID-19 vaccine or no COVID-19 vaccine. Read more about this study
- Who is it for?
- Ages 50 to 64 yearsHealthy volunteers can take part
- Conditions the study is for
- COVID-19
- What is being tested?
- mRNA-1273 (Moderna COVID-19 vaccine)
- Type of treatment
- Vaccines, Injection or infusion
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 41,060 participants
- Where
- 2 sitesDenmark
- Study dates
- 11 Dec 2025to 5 Sep 2026
- Phase
- Phase 4
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 50 to 64 years
- All sexes
- Healthy volunteers accepted
- Adult
Who may be able to join
- Age 50-64 years
- Informed consent form has been signed and dated
Who cannot join
- Medical conditions that increase the risk of severe COVID-19, which will be assessed through self-reporting. These medical conditions include:
- Asthma
- Cancer (excluding non-melanoma skin cancer)
- Cardiomyopathies
- Cerebrovascular disease
- Chronic kidney disease
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- Chronic lung disease
- Cystic Fibrosis
- Dementia
- Diabetes
- Down syndrome
- Heart failure
- Human Immunodeficiency Virus
- Immunosuppressive therapy
- Ischemic heart disease
- Liver disease
- Neurological/neuromuscular disease
- Psychiatric disease (psychotic, schizophrenic, schizotypal, depressive, and bipolar (affective) disorders).
- Severe obesity (body mass index >35 kg/m2)
- Severe substance abuse
- Short bowel syndrome
- Solid organ transplant or hematological transplant
- Apart from these, there are no specific exclusion criteria for this study
Trial locations and contacts
2 sites in 1 country.
Denmark2 sites
Center for Translational Cardiology and Pragmatic Randomized Trials, Department of Cardiology, Copenhagen University Hospital - Herlev and Gentofte
Hellerup, 2900
Danske Lægers Vaccinations Service
Søborg, 2860
About this study
Official title: A Phase 4 Pragmatic, Randomized Trial to Evaluate the Effectiveness of mRNA-1273 Variant-Containing Vaccine Formulation Against Severe Outcomes in Adults Aged 50-64 Years Without Risk Factors for Severe COVID-19
The purpose of this pragmatic randomized trial is to evaluate the vaccine effectiveness of the COVID-19 vaccine, mRNA-1273, in adults aged 50-64 years without known risk factors for severe COVID-19 infection. Participants will be randomized 1:1 to either COVID-19 vaccine or no COVID-19 vaccine.
Read the detailed description
The study is a pragmatic, registry-based, open-label, individually randomized trial. The Danish nationwide administrative health registries will be used for data collection including baseline information, follow-up data, and safety monitoring. The study aims to randomize a total of 285,000 participants. Participants will be individually randomized 1:1 to receive either a COVID-19 vaccine or no COVID-19 vaccine. The study is designed to assess the vaccine effectiveness of the COVID-19 vaccine vs. no COVID-19 vaccine on the risk of medically attended COVID-19 infection.
- Conditions
- COVID-19
- Being tested
- mRNA-1273 (Moderna COVID-19 vaccine)
- Keywords
- COVID-19, Vaccination, Pragmatic, Registry, Respiratory tract disease, Respiratory, Cardiovascular
- Medical subject headings
- COVID-19, Respiratory Tract Diseases
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
mRNA-1273 (Moderna COVID-19 vaccine)Biological
For this arm, the current variant formulation of Spikevax (mRNA-1273) vaccine will be used.
| Study group | Role | What they receive |
|---|---|---|
| mRNA-1273 (Spikevax) | Experimental | COVID-19 vaccine single injection at day 0 Receives: Biological: mRNA-1273 (Moderna COVID-19 vaccine) |
| No COVID-19 vaccine (control) | No intervention | Control arm, no COVID-19 vaccine |
What is being measured
The primary outcome is the main question the study is designed to answer.
Medically attended COVID-19
Defined as a positive PCR test for SARS-CoV-2 or hospitalization for COVID-19-related respiratory tract disease
Measured: ≥14 days after initially booked study visit date until 6 months after initially booked study visit date
Secondary outcomes (9)
COVID-19-related hospitalization
Measured: ≥14 days after initially booked study visit date until 6 months after initially booked study visit date
COVID-19-related respiratory tract disease hospitalization
Measured: ≥14 days after initially booked study visit date until 6 months after initially booked study visit date
COVID-19-related cardio-respiratory disease hospitalization
Measured: ≥14 days after initially booked study visit date until 6 months after initially booked study visit date
All-cause respiratory tract disease hospitalization
Measured: ≥14 days after initially booked study visit date until 6 months after initially booked study visit date
All-cause cardio-respiratory hospitalization
Measured: ≥14 days after initially booked study visit date until 6 months after initially booked study visit date
All-cause lower respiratory tract disease hospitalization
Measured: ≥14 days after initially booked study visit date until 6 months after initially booked study visit date
All-cause hospitalization
Measured: ≥14 days after initially booked study visit date until 6 months after initially booked study visit date
COVID-19 death
Measured: ≥14 days after initially booked study visit date until 6 months after initially booked study visit date
All-cause death
Measured: ≥14 days after initially booked study visit date until 6 months after initially booked study visit date
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted12 Dec 2025
- Study start11 Dec 2025
- Primary completion26 Aug 2026
- Study completion5 Sep 2026
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for COVID-19Studies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 4
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Enrolment
- 41,060 participants (actual)
Sponsor and investigators
- Lead sponsor
- Tor Biering-Sørensen
- Sponsor type
- University, hospital or other
- Collaborators
- ModernaTX, Inc.
- Responsible party
- Sponsor-investigator, Tor Biering-Sørensen, Herlev and Gentofte Hospital
- Investigators
- Tor Biering-Sørensen, MD, MSc, MPH, PhD, Study chair, Center for Translational Cardiology and Pragmatic Randomized Trials, Department of Cardiology, Copenhagen University Hospital - Herlev and Gentofte
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07279766
- Sponsor's protocol ID
- DAN-COVID
- Other IDs
- 2025-523841-82-00, 2025
- Acronym
- DAN-COVID
- Status last verified
- Oct 2026
- First submitted
- 28 Nov 2025
- Last updated
- 6 Oct 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes: In this trial, baseline and endpoint data will be collected from Danish administrative health registries, which are subject to Danish legislation and can only be made available to a third party under certain conditions. Please contact the sponsor-investigator in case of any inquiries.
Study at a glance
From the registry record, last updated by the sponsor on 6 Oct 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Phase 4 Pragmatic, Randomized Trial to Evaluate the Effectiveness of mRNA-1273 Variant-Containing Vaccine Formulation Against Severe Outcomes in Adults Aged 50-64 Years Without Risk Factors for Severe COVID-19
- ClinicalTrials.gov ID
- NCT07279766
- Acronym / sponsor ID
- DAN-COVID / DAN-COVID
- Conditions
- COVID-19
- Keywords
- COVID-19, Vaccination, Pragmatic, Registry, Respiratory tract disease, Respiratory, Cardiovascular
- Phase
- Phase 4
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 41,060 participants (actual)
- Lead sponsor
- Tor Biering-SørensenUniversity, hospital or other
- Collaborators
- ModernaTX, Inc.
- Study start
- 11 Dec 2025 (actual)
- Primary completion
- 26 Aug 2026 (actual)
- Study completion
- 5 Sep 2026 (actual)
- First posted
- 12 Dec 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The purpose of this pragmatic randomized trial is to evaluate the vaccine effectiveness of the COVID-19 vaccine, mRNA-1273, in adults aged 50-64 years without known risk factors for severe COVID-19 infection. Participants will be randomized 1:1 to either COVID-19 vaccine or no COVID-19 vaccine.
Detailed description
The study is a pragmatic, registry-based, open-label, individually randomized trial. The Danish nationwide administrative health registries will be used for data collection including baseline information, follow-up data, and safety monitoring. The study aims to randomize a total of 285,000 participants. Participants will be individually randomized 1:1 to receive either a COVID-19 vaccine or no COVID-19 vaccine. The study is designed to assess the vaccine effectiveness of the COVID-19 vaccine vs. no COVID-19 vaccine on the risk of medically attended COVID-19 infection.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| mRNA-1273 (Spikevax) | Experimental | Biological: mRNA-1273 (Moderna COVID-19 vaccine)COVID-19 vaccine single injection at day 0 |
| No COVID-19 vaccine (control) | No intervention | –Control arm, no COVID-19 vaccine |
Who may qualify
- Ages
- 50 to 64 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (2 listed)
- Age 50-64 years
- Informed consent form has been signed and dated
Key exclusion criteria (23 listed)
- Medical conditions that increase the risk of severe COVID-19, which will be assessed through self-reporting. These medical conditions include:
- Apart from these, there are no specific exclusion criteria for this study
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| mRNA-1273 (Moderna COVID-19 vaccine)For this arm, the current variant formulation of Spikevax (mRNA-1273) vaccine will be used. | Biological | mRNA-1273 (Spikevax) |
Primary outcome
Medically attended COVID-19
Time frame: ≥14 days after initially booked study visit date until 6 months after initially booked study visit date
Defined as a positive PCR test for SARS-CoV-2 or hospitalization for COVID-19-related respiratory tract disease
9 secondary outcomes
COVID-19-related hospitalization
Time frame: ≥14 days after initially booked study visit date until 6 months after initially booked study visit date
COVID-19-related respiratory tract disease hospitalization
Time frame: ≥14 days after initially booked study visit date until 6 months after initially booked study visit date
COVID-19-related cardio-respiratory disease hospitalization
Time frame: ≥14 days after initially booked study visit date until 6 months after initially booked study visit date
All-cause respiratory tract disease hospitalization
Time frame: ≥14 days after initially booked study visit date until 6 months after initially booked study visit date
All-cause cardio-respiratory hospitalization
Time frame: ≥14 days after initially booked study visit date until 6 months after initially booked study visit date
All-cause lower respiratory tract disease hospitalization
Time frame: ≥14 days after initially booked study visit date until 6 months after initially booked study visit date
All-cause hospitalization
Time frame: ≥14 days after initially booked study visit date until 6 months after initially booked study visit date
COVID-19 death
Time frame: ≥14 days after initially booked study visit date until 6 months after initially booked study visit date
All-cause death
Time frame: ≥14 days after initially booked study visit date until 6 months after initially booked study visit date
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 6 Oct 2026.
- Individual participant dataSharing planned: Yes. In this trial, baseline and endpoint data will be collected from Danish administrative health registries, which are subject to Danish legislation and can only be made available to a third party under certain conditions. Please contact the sponsor-investigator in case of any inquiries.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Tor Biering-Sørensen, MD, MSc, MPH, PhD study chair
Center for Translational Cardiology and Pragmatic Randomized Trials, Department of Cardiology, Copenhagen University Hospital - Herlev and Gentofte
2 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 4 study testing mRNA-1273 (Moderna COVID-19 vaccine) in people with COVID-19, run by Tor Biering-Sørensen at 2 sites in Denmark.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 2 inclusion and 23 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 6 Oct 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 2 sites in Denmark. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 4 studies take place after a treatment is approved, to learn more about its long-term benefits and risks in everyday use.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Medically attended COVID-19 (time frame: ≥14 days after initially booked study visit date until 6 months after initially booked study visit date). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 6 Oct 2026.